Laser Module Signal Voltage Mismatch Diagnosis

To determine if a voltage mismatch exists between the GRBL control board and the laser module, use a multimeter to measure the PWM signal output while the controller is set to a constant power state. Connect the multimeter's black lead to the board's GND and the red lead to the PWM output pin. If the measured voltage is outside the operating range required by your specific laser driver (e.g., measuring 3.3V when the module requires a 5V logic signal, or observing no signal transition during power-up), the signal is incompatible.

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